Install excepthook for top-level errfile

.github/workflows/tests.yaml

@@ -22,7 +22,7 @@ jobs:
         python -m pip install pytest
     - name: Run tests
       run: |
-        python -m pytest tests
+        python -m pytest tests -vv -s
     - name: Package installation
       run: |
         python -m pip install portal

portal/__init__.py

@@ -1,4 +1,4 @@
-__version__ = '3.1.11'
+__version__ = '3.1.12'
 
 import multiprocessing as mp
 try:

portal/contextlib.py

@@ -61,6 +61,7 @@ def setup(
       assert hasattr(errfile, 'exists') and hasattr(errfile, 'write_text')
       self.errfile = errfile
       self._check_errfile()
+      self._install_excepthook()
 
     if interval:
       assert isinstance(interval, (int, float))
@@ -148,6 +149,16 @@ def _watcher(self):
     while not self.done.wait(self.interval):
       self._check_errfile()
 
+  def _install_excepthook(self):
+    existing = sys.excepthook
+    def patched(typ, val, tb):
+      if self.errfile:
+        message = ''.join(traceback.format_exception(typ, val, tb)).strip('\n')
+        self.errfile.write_text(message)
+        print(f'Wrote errorfile: {self.errfile}', file=sys.stderr)
+      return existing(typ, val, tb)
+    sys.excepthook = patched
+
   def _check_errfile(self):
     if self.errfile and self.errfile.exists():
       message = f'Shutting down due to error file: {self.errfile}'